The invention refers to a device for activating a locking or adjustment device placed inside the shell of a helmet for the purpose of attaching, securing, detaching, or adjusting a cheek strap by means of a manually accessible handle on the outside of the helmet. Such operating devices serve to open or close cheek straps on crash helmets or protective helmets, primarily for motorcycle drivers. But for helmet shells with several parts and/or helmet shells which can be swung upwards, there is a necessity to be able to operate the plug-type connection from the outside by means of a device for e.g. opening or locking it.
In known adjustment or closing devices which are fixed on the helmet side, notches are provided on the side of the helmet shell, in which pull or push keys are accessible for operating the closing or adjustment devices for the cheek strap. Due to the required accessibility of these safety devices--for instance, they must be operable with the thumb of a gloved hand--the openings in the helmet shell must be correspondingly large.
In the practice, this leads to e.g. the following disadvantages:
1. During driving at high speeds, very strong noise occurs, which might even cause damage to the hearing;
2. It is difficult to close the openings against wetness penetrating form the outside;
3. In order to ease operation, the manual controls must be designed as depressions, whereby, in the case of certain depression shapes, the danger of them being caught on something in case of a fall cannot be wholly eliminated.